Apparatus for producing dried milk.



C. H. CAMPBELL.

APPARATUS FOR PRonucmG 0mm MILK.

APPLICATION PILU) APH. 1l. 19H.

1,292,577. Patented Jan. 28,1919.

c. H. CAMBELL. APPARATUS FOR PHODUCING DRIED MILK.

APPLECAUGN LED APR. It, |917. A 1,292,577. Patented Jan. 28, 19m.

4 SHEETS-SMU 4.

STATES PATENT oEEIoE.

snm., or NEW Yoan, N. Y., Assronon To nonDnNs connnNsnn Y Y @rimioonrnirm or Nnw rome, N. Y., s coaronarron or NEW messy.

APPARATUS FOB PROBUCING BRIE@ MILK.

Specification of Letters Patent.

Patented Jan. es, 191s.

Original plleation illed December 21, 1915, Serial NQLBZBSB. Patent No. 1,233,446, dated July 17, 1917.

mvled and this application filed April 11, 191'?. Serial No. 161,147.

To it concern:

Y Y it n that I, CHARLES H. Cesrr Hillier-:citizen of the United States, residv g the., borough of Manhattan, city,

m Statemf New York, have invente Yncrv and usefulV Improvements in A'p- Y@craters Brodung Dried Milk, oi Wlnc'h the volorvn is a specification, this application beings, vision of my application Serial No. ,99rlA ed December 21, 1915, on which Y srasl'z granted Patent No. 1,233,446, July 17,

inventionV relates to apparatus for pro ucing dried or desiccated milks, Vand its objects comprise provision of means in aid of an industriali Y,practifnble procedure, the final producto which is composed solely @constituents of the natural milk, whence it isrderived, and which, as compared with any other mlks known to me, is more rapidly perfectly soluble in Water, which, asV thus reconstituted, possesses more Vnearly and periectly all the desirable charadaeristics Yand Y behaviors of natural milk, and the peptcgenic properties ot which are even more eective than those of the natural,

VFigure l is aside view, largely 1n section, of nryaerat' andstirring devices.

25872: eta perspective view of one 'of Y.stlrrers isolated.

3 is, on enlarged scale, a cross scctionslverron line33 of Fig. 1 viewed in of the arrow.

l i, a. view on line T--T of @ed inthe direction of the arrow, i the for holding the rewesten sa@ new er the een Y.disposition thereon of the @inference numerals and letters refer tolike parts in the respective figures.

' method of producing my dried milk 4s.' Eig.

' produce pioduct is as follows: I iirst procure, or

in any convenient Way, a concentrate ,of normal, uid, skimmed, milk. l have discovered thaJ it is essential for requiste viscosity that the albumin of Such concentrate berruncoagulated, and it is preferable thatall of its other constituents retain likewise their normal characteristics and qualities as in the natural milk.

Such concentrate is producible by such method and means as are disclosed in Letters Patent No. 668,161, dated February 19, 1901, to Joseph H. Campbell, or in my Ylending application Vfor Letters Patent serial Nos. 781081, iled July 25th, 1913, and 865,647, sied october sa, 1914, in which, by aid of blowing air through the milk, itV is concentrated so rapidly as to avoid undesired changes of its constituents.

l have Yalso discovered that in order to produce the most desirable form of my dried product, it is preferable that the milk be thus concentrated down to not less than onethird, and preferably down to about onesixth, of its original volume.

This concentrated milk thus obtained, I next serate, in such manner, as to pervasively and homogeneously occlude, throughout the mass, the greatest possible number of se arated, relatively minute, bodies of air, there y pervadincr the semi-liquid viscous concentrate of milk solids by a great number of mutually, closely approximated relatively minute and persistent spherical cells, whereby a substantially infinite number of curved interior surfaces are imparted to the mass.

Such aeration I accomplish by injecting into the concentrate, air, or other suitable as, under pressure, and meanwhile stirring YYt e commingled air and concentrate, the

multitude of small gas-containing cells thus crwatcd therein.

The instrumentalities employed to thus stir, should be of such form and operation as to continuously displace, distort, and break up therewith contacting portions of the viscid concentrate, and of thereagainst bearing bodies of compressed gas, whereby is secured the desired multiplication and minutencss of the subdivisions of the latter in the concentrate.

I have invented in aid of thus aerating the thus concentrated milk, the combination of devices shown in Figs. 1, 2 and 3 of the drawings, in which 12 represents a suitably stationarily supported, longitudinally eX- tended, tank or container, for the concentrated milk, divided by partitions 12 into a series of alike intercommunic'ating chambers, and preferably provided with any suitable rover 122 and with an ordinary jacket, or jackets, 13, connected in the usual manner, or by suitably valved conduits 13 with the usual sources (not shown) of temperature influencing mediums, and provided as of course with the usual outlets 132.

Into each compartment, adjacent the bottom thereof, means are provided for injecting thereinto compressed air, or other suitable gas, these being, in this instance, the conduit pipes 11 leading to a suitable source of supply (not shown) and each provided with a valve 14: whereby the volume admitted may be regulated as required.

Incidentally, I prefer to also connect the said pipes with a steam supply, as per the branch pipe 142 (Fig. 3) provided with a valve 11 whereby the temperature of the compressed air may be raised if desired.

A pipe 15 (Fig. 1) coimecting,r the interior of one end of the tank with any suitable source of supplv of the concentrated milk, and provided with a valve 15, affords means for charging the tank as and when required. Another pipe 1G provided with a valve 16' affords an outlet for the concentrate after its treatment in the tank.

lntercommunication between the chambers, such as to enable the milk to How sequentially through the series, is provided, in this instance, by means of openings 17 (Fig. 3) in each of the partitions, the aperture of which is variable as required, by means of removable bars 17 slidably held by aid of guide flanges 172 (Fig. 4) carried by the partition adjacent the vertical sides of the opening, the height of the opening being proportional to the number of said bars at any time so held across it.

A rotatory shaft 18 is mounted in the sides of the tank and its partitions, and provided with the usual pulley 18', belt 182, and other `connections with a source of power (not shown).

The shaft 1S carries within each of the chambers a stirring or mixing device 1f? (Fig. 2), in this instance, composed of a plurality of mutuall -parallel attenuated rods 19 preferably a out one-quarter inch diameter, carried by frames 192 secured to the shaft.

The construction is such that, as follows from the foregoing, means are provided whereby the temperature in some of said chambers relatively to the temperature in others is variable by the operator as may be indicated; likewise the volume of gas injected into any chamber as compared to another; also means are provided whereby the feed of milk into the first in series, and the discharge of aerated milk from the last in sequence, of said chambers is likewise variable.

These features are of great importance because during the latter stages of aeration a lower temperature and injection of gas in greater volume than during the earlier are, in connection with other features described, conducive, if not indispensable, to attainment of my aforesaid peculiarly aerated product in its best form.

The operation is as follows: The aforesaid concentrated milk is admitted through pipe 15 in quantity sufficient to fill the first compartment. The valve 14 being now opened, compressed air is then injected thereinto and the shaft 18 simultaneously rotated. The rods are thus caused to constantly, momentarily, divide therewith contacting portions of the viscous concentrate. and of the air bodies therein in motion. This results in an intimacy and completeness of mixture of the air and concentrate otherwise unattainable, and the concentrate being sutliciently viscous, the very minute subdivisions of air, or bubbles, are thereby persistently retained, as compared with otherwise larger occlusions of air. As the operation proceeds the feed of concentrate is continued, and the overflow passes through the openings in the partitions sequentially through each sures, or the moderate disturbing influ-` ences to which exposed by the next step of my method. During the operation there is circulated through the jacket 13 and its connections, the usual How of a temperatureinfluencing medium, such as heated water, but in order to preserve the milk constituents unchanged, and, particularly at this stage, the viscosity of the concentrate, the tempera ture should not be raised above that of the coagulating point of albumin. My next step consists in dehydrating or extracting from, my, at this stage, aerated batter substantially all of its remaining moisture, or suiiiciently to produce my nal dried product. From the outlet pipe 16 the batter is conveyed in any convenient manner and spread in a layer of uniform thickness upon Va forwarding instrumentality, adapted to expose the greatest surface thereof with least dlsturbance to the therein occluded bubbles.

have discovered that these requirements are best subserved by using assuch instrumentality, an endless carrier m the form of an air-permeable yielding belt 20 (Figs. 5-8), composed, in this instance, of nineteen gage wire two and one half mesh.

This-belt is carried and endlessly forwarded in the direction ofthe arrow, in the usual manner, as by aid of pulleys 21, 2l, (Fig. 5) and other mstrumentalities not shown. Adjacent one of these pulleys, I support, stationarily, over the belt, a ree? tangular storage hopper 22 (Figs. 5 and 6) beneath the open bottom of which I stationarily support a licor or bottom 23 with which the lateral sides of thehopper conthe hopper transverse the belt, are preferably inclose as shown in Fig. 6, and provided with inclined plates 22 and 22b adjustable in any convenient manner, as by set-screws 220 and 22", so that their edges may be approximated and held, in required relation to the top of the belt, which passes between them and said floor These plates, or at least their belt-approximating edges, posed of flexible or to an material. The out et p' 16 vents into the hopper, as sh lgig. 6. The construction is such that Some of the aerated batter concentrate, D, is constantly accumulated upon the belt within the connes of the hopper. By adjustin the proximity of the lower edge of the p ate 22'L tothe top ofthe belt, a uniform desired thickness 1s extent, yielding inasmuch as without it, it is impossible to uniformly with desired rapidit all portions of the belt-carried batter. he plate 22 should be adjusted to as close contact with the belt and door as is permissible without undue of movement.V

is not only to close that side of the hopper against undue leakage of the batter, but also to wipe 0E of the thereunder-advancing belt any articles of thereto still adherent dried milg.

The relative dispositions of the belt and its thereto adherent layer of aerated batter,

should be cominto a removal chamber 26 kstromen:

in the layery are indicated in Fig. 8', in which the layer and the war wires are shown in section, andthe woo wires in perspective.

e belt, as it advances, carries the layer into a d g chamber 24, where it p as shown, between an extended series of oEpositely-disposed, stationarily supported, a ke, driers 25, consi of avreservoir and 25",

propel the air. Each reservoir is open toward' the Ibelt, but in order to uniformity of distribution and to avoid an rbing air pressures against the batter, I prefer to interpose over the o screen 25c of moderately open mVV and, to the Same end, to iner'pse medial in the reservoir another likeY screen 25 of somewhat larger mesh. By these means a constant outbreath of heated air is simul taneoasly applied to both sides of the la er of b atter, but so diusedly and gently at the integrity of the air bubbles in the batter is not destroyed, or jeopardized, as might if the ordinary hot air blasts of the art were employed.

I prefer that the drying should be accomp ished wlthout raising the temperature so gh as to coagulate the albumin,

e emical characteristics of the other milk 'ds and constituents other than water. Y

The thus= rapidly and'uniformly drying batter is, by t e belt, conveyed within the drying chamber, around the pulley 21* and thus out of the chamber. Thence it p t 5), where 1n any convenientV instrumen ties can be operated to remove the now dried product from the belt. I h stance diigrammatically indicated such ine, ities as Scrapers 2T, supp and Vdisposed to Iyieldingly scrape the roduct oil of the be t, also as coactlng ro 28 28. These instrumentalities olf of the belt in Hake-like forms, or groups, most of the thereto adherent, now dried, milk solids.V These fall by avityV to the bot tom of the chamber, wxence 'they may` be removed, for use, by any well known means. E provide adjacent the main er an auxiliary chamber 29 for collection, therein, of minute particlfsY of the dried solids which may still adhere, .to the belt, and which are of though less desirable commercial product, these minute particles, though more rapidi any driedl mil chamber 29 I brush th fbelt thorou bly, usin in this instance, cylindrical revel7 brus es 30, 30', of type too familiar to require further description here. The belt V'ng aI ving Y plurality emerges from the chamber 29 substantially cleansed of all thereto-adhering particles, passes over the pulley 21 and returns to its original position beneath the hopper 22, and the cycle is indefinitely repeate It will be noted that throughout the operations described, care is taken to exempt the aerated batter, until dried, from any shocks or pressurescapable of seriously disrupting its integrity and continuity, or of causing the therein occluded air globules to disrupt or escape from the still plastic magma constituting their matrix. But the constitution imparted to that magma by the preceding procedures and treatment is such that it is suiciently viscous and tenacious to endure all the ordinary strains incident to the operation, without releasing its occluded air. In this, it differs notably from anything producible by merely beating or otherwise converting raw milk, or even concentrated milk, into mere froth or foam. I am aware that it has been suggested that milk be so frothed or foamed by beaters, and the resulting foam or froth dried, but this I have found impracticable because of the instability of the large bubbles thus produced, and the impossibility of thus homogeneously and persistently aerating the milk treated.

The rods 19 are preferably cylindrical, t'. e. of circular cross section, their function being tc continuously slice or cut smoothly and evenly, in a multitude of planes, the viscid concentrate through which the air is being upwardly and relatively gently forced, and thus produce the desired impregnation with the least possible ebullition from the surface. To this end, the mixing device 19 is preferably maintained at all times completely immersed in the concentrate thus avoiding any spasmodic heating into the latter of uncontrollably irregular volumes of surface air.

The dimensions of each of the intercommunicating chambers of the tank 12 may, in the specimens shown in the drawings, be taken to be 12 inches square by 30 inches deep. The tops of the openings 17 are about 18 inches above the floor of the chambers. These dimensions will, of course, be varied according to circumstances, and mention them only as a guide to approximately pro er proportions.

Having t us described my inventiomwhat I claim and desire to secure by Letters Patent isA the following: A

1. In an apparatus for treating milk, a of chambers interconnected by a athway for the milk, means to inject as into, and stirring means in, each of a p urality of said chambers.

2. In an apparatus for treating milk, a plurality of chambers interconnected by a pathway for the milk, means to inject gas into, and stirring means in, each of a plurality of said chambers, and means to vary the temperature in one of said chambers relatively to the temperature in another.

3. In an apparatus for treating milk, a plurality of chambers, a partition between each mutually adjacent pair thereof provided With an opening located between the top and bottom of said chambers, means to inject gas into, and stirring means in, each of a p urality of said chambers.

4. In anU apparatus for treating milk, a series of like chambers interconnected by a pathway for the milk; a rotatory shaft mounted in said chambers; a pluralit of agitating members carried by said sha in each of said chambers, and means to inject gas into said milk in each of said chambers.

5. In an apparatus for treating milk, a plurality of chambers interconnected by a pathway for the milk, means to inject gas into, and stirring means in, each of said chambers, and means to vary the volume of gas so injected into one of said chambers relatively to the volume so injected into another.

6. In an apparatus for treating milk, a plurality of chambers interconnected by a pathway for the milk, means to inject gas into, and stirring means in, each of a plurality of said chambers; means to vary the tem erature in one of said chambers relative y to the temperature in another; and means to vary the volume of gas so injected into one of said chambers relatively to the volume so injected into another.

7; In an apparatus for treating milk, a plurality of chambers interconnected bv a pathway for the milk, means to inject gas into, and stirring means in, each of a plurality of said chambers; means to vary the temperature in one of said chambers relatively to the temperature in another; means to vary the volume of as so injected into one of said chambers re atively to the volume so injected into another; means to feed the milk into the irst in series of said chambers; means to regulate said feed; means to discharge the aerated milk from the last in sequence of said chambers; and means to regulate said discharge.

8. In an apparatus for treating milk, a plurality of chambers, a partition between each mutually adjacent pair thereof provided with a variable opening located between the top and bottom of said chambers, means to inject gas into, and stirrin means in, each of a plurality of said cham ers.

9. In an apparatus for treating milk, a series of horizontally side-by-side intercommunicating chambers for the milk; a rotatory shaft mounted in said chambers, a plurality of airs of parallel arms carried by said sha t in each of said chambers and projecting radially from said shaft at right angles thereto; a plurality of rodscarried b eaeie said pair of arms in arallelis'm wit said shaft and with each ot er, and means to in ject gas into each of said chambers below the path of said rods. l ,Y 10. In an apparatus for treating concentrated milk, a covered chamber havin an openin inV one side, between the top and ct'- tom, t ereof; a rotatory horizontally disposed shaft mountedv in said chamber; a piu'- Y rality of pairs of parallel arms, carried by and means te inject gas into Y Shepath of said agitator in said chamber.

12.7 In an apparatus for sei-ating concentrates, a consecutive sones of chambers 1n- V tierconnected by a pathway, for the concentrate, extending above the bottom of said chambers; means for aerating the concentrate in each of a plurality of said chambers independently of the others; means to continuousiy supply the concentrate to the first of said series of chambers; and means to withdrawfthe aerated concentrate from the last in series of said chambers, whereby the more aerated andfrisin portions of the concentrate in each cham er are progressively withdrawn therefrom and further aerated in another of said chambers apart from less aerated portions of the concentrate.

. CHARLES H. CAMPBELL.

Witnesses:

TIMOTHY J. MAHONEY, D. Hannan BUSH. 

